Artificial-tooth construction



Feb. "12, 1929. 1,702,212

A. B. JOHNSON ARTIFICIAL TOOTH CONSTRUCTION Filed Oct. 16, 1925 Patented Feb. 12, 1929.

UNITED STATES ALBERT B. JOHNSON, OF HARTFORD,

CONNECTICUT.

ARTIFICIAL-TOOTH CONSTRUCTION.

Application filed October 16, 1925. Serial No.

My invention relates to improvements in artificial tooth construction, involving the grinding off of material from a portion only of the exposed surface of a tooth of porcelain and the application to said ground off portion of porcelain paste and the use of heat for fusing parcel ain from said. paste, uniting the same to the tooth body, and the object of my improvement is to disclose means for efiecting this result that are relatively simple, reliable, and eiiicient, whereby said ground off portion or zone will be coated with a deposit of porcelain in the form of a film or veneer, and which presents a surface or face that will usually be distinguishable in appearance the exposed surface of the adjacent body portion that is in the original condition.

In the accompanying drawing z- Figure 1 is a front elevation of a set of artificial teeth in which are incorporated certain individual teeth embodying my invention.

Figure 2 is a front elevation of one of said individual teeth, being the first or front and left incisor shown in Fig. 1, and on an enlarged scale.

Figure 3 is a front elevation of the same be fore being operated upon by grinding.

Figure 1 is a similar view of the same after grinding.

Figure 5 is a similar view after the deposit of porcelain from paste in the ground off portion or zone.

Figures 6, 7 and 8 are sectional views respectively on the correspondingly indicated lines of Figs. 2, 4, and 5.

My improved artificial tooth construction is illustrated in the of artificial teeth, the set being an upper set with the individual teeth incorporated in the late 11 of the usual form.

Said individual teeth comprise as determined from the front and on each side the first or front incisor 12, the second incisor 13, and he canine teeth 14. Then come the premolars and the molars.

Certain of the teeth specifically mentioned have a. portion of the exposed surface or a. zone that is marked off or defined by a line of division between the same and the adjacent surface of the body portion, the tinting or shading being slightly different for the two sides of the line.

The body portion or present instance by a set 10' tooth proper is made of porcelain; is the initial condition in the form in which it is received from the manufacturer for the use of the dentist, being a. complete tooth adapted to be inserted in the plate; is operated upon by grinding to the extent of the zone determined upon by the 0 erator; a layer of porcelain paste is a plie to the ground-off portion; baking fol ows, involving fusing of the paste and also a shrink age thereof; and, there may be repetitions of the application of the paste and baking.

These details will now be considered with reference to a selected tooth, being the front and left incisor 12, having the body portion 15 and terminating at the lower left side in the corner 16. i

he zone 19 at and adjacent the lower right hand corner and indicated in Fig. 4; is the portion that is ground off and is defined by the border edge 18, Figs. 6, 7, and 8.

In Figs. 2 and 6 the character 17 indicates the deposit of porcelain from paste in the ground off zone 19 and which substantially the entire may be obtained from a application or may tion.

The character 17 in Figs. 5 and 8 indicates a partial deposit only and a second treatment would be desirable to complete the coatingof the zone 19.

deposit covers zone. This result single treatmentor follow a second applica- For the baking an electric furnace is preferably employed.

The material deposited has substantially the same characteristics as that of the body portion and the junction between the two 1s substantially of integral character.

I find that the new porcelain of the paste melts on the old portion in a manner similar to the way in which 18k. gold melts on 14k.

gold.

I claim as my invention In artificial tooth construction, providing a tooth of parcelain, removing the surface layer of a portion of said tooth to the extent of a zone that is appreciably smaller in area than the area of the, exposed face of said tooth, applying to said zone a layer of porcelain paste, and heat-treating said tooth with the paste so applied thereto in a furnace so as to melt said paste and form an integral coating of the melted material for said zone.

" ALBERT B. JOHNSON. 

